Hemizygous TorsinKO78 flies survive through larval stages and most die during pupation, and they spend significantly more time in the third instar larval stage than controls. Hemizygous TorsinKO78 third instar larvae display a significantly smaller fat body, and reduced body weight, but no overall different in body size; fat body cells are smaller due to a failure to undergo expansion during larval stages; lipid droplet size is increased in early L3 fat cells and lipid droplets are often fused in late L3 fat cells, but there is no obvious change in lipid droplet density; tubular ER structures appear to be missing; as compared to controls.
Mutant muscle and epithelial cells have large ribonucleoprotein (megaRNP) granules tethered to the inner nuclear membrane.
The number of normal synaptic boutons at the neuromuscular junction is significantly reduced in mutant third instar larvae compared to wild type, while the number of undifferentiated 'ghost' boutons is significantly increased.
Only a few TorsinKO78/Y adult males survive. These are sterile, have a pale body colour, have short and thin bristles, and move slowly.
Dopamine levels are significantly reduced in adult heads of TorsinKO13/+ adult females compared to wild type. The levels of the dopamine metabolite DOPAC are also decreased in TorsinKO13/+ adult female heads, though not proportional to the reduction in dopamine levels.
Heterozygotes show no significant difference in tyrosine hydroxylase activity, but do show a significant reduction in GTP cyclohydrolase activity, compared to wild type controls.